There has been a long felt need for providing data received during use of radar of the Plan Position Indicator type (PPI) in an improved display. The prior art direct displays utilized with PPI radar systems, usually in aircraft, have suffered from annoying windshield wiper effects as well as low brightness.
In one prior art attempt to improve the display of a sector scan radar PPI signal, the signal or data was first displayed on a conventional radar display device to provide a visual display, which display was read by a television type camera and reproduced on a conventional type of television display, much in the manner of a closed circuit television system.
In another prior art attempt to improve or enhance the display of a sector scan radar PPI signal, a scan converter tube utilizes one electron beam to store representation of the radar PPI signal upon an appropriate storage surface, such as is well known in the art, in a polar coordinate format, which polar coordinate format stored signal is then read from the storage surface in a cartesian coordinate format by an electron beam scanning the stored representation of the PPI signal.
Both of the foregoing attempts to improve the radar signals display by converting the originally received radar signal to a cartesian format suffer from inherent problems. One inherent problem relates to the time constants of the elements such as phosphors utilized in the conversion process from a polar to a cartesian format. Another inherent problem resides in the failure to produce the high resolution essential for optimum information display.